I need a USB 3.0, 1TB external HD to backup my files. I have amazon gift credit, so something in the $70-90 range from amazon would be preferred unless there is a really good deal somewhere else. There's a lot of choices, so I appreciate any suggestions.

Check out Microcenter or TigerDirect. They both have retail stores as well as online stores. Their online price and store price are a little different, so if you see no sales online, they might have in store. Both of those are located in Chicago, I know.

But, if you want Amazon, get those WD My Passport (whatever color you like). My sister-in-law has a 320GB passport and loves it.